B. hyodysenteriae leads to diarrheal disease in growing pigs worldwide, causing the so-called swine dysentery, typhlocolitis or porcine intestinal spirochaetosis, which contributes to major "production losses" in agrobusiness.

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN)[6] and National Center for Biotechnology Information (NCBI).

Publications now tend to point out that Brachyspira colonization should not be considered harmless commensalism: Treatment with 10 days co-amoxicilline 1g bid + metronidazole 500 tid seems to have very good results on abdominal symptoms.

[citation needed] Veterinary antibiotics used to treat pigs with dysentery due to Brachyspira species include the lincosamide lincomycin, the ionophore salinomycin, the quinoxaline carbadox, the pleuromodulins tiamulin and valnemulin, as well as the aminoglycoside gentamicin, an important antibiotic used in humans.

While no Clinical and Laboratory Standards Institute (CLSI) antimicrobial breakpoints for Brachyspira have been established, resistance to the pleuromodulins tiamulin and valnemulin is considered at MIC ≥ 2 μg/ml.

[31] Recently quantitative PCR seems to be a more sensitive way to identify Brachyspira, which is globally a very fastidious bacterium to grow.

A compelling explanation for this change in epidemiology and ecology is selection by the increasing use of antibiotics in pigs (e.g. as growth promoters), since B. murdochii and unclassifiable Brachyspira spp.